Merocyanine dyes



2,865,917 IVIEROCYANINE DYES Douglas James Fry, Bernard Alan Lea, and John David Kendall, Ilford, England, assignors to Ilford Limited, Ilford, England, a British company No Drawing. Application August 5, 1957 Serial No. 676,383

application Great Britain August 17, 1956 6 Claims. (Cl. Mil-240.4)

Claims priority,

This invention relates to merocyanine dyes, their production and use.

According to the present invention there are provided merocyanine dyes of the general formula:

naphthyl methyl. Where alkoxy these are preferably lower alkoxy or ethoxy.

Thus the values of the various symbols may be stated as follows: R and R are each selected from the class consisting of lower alkyl groups, benzyl, naphthyl methyl, thyl halophenyl, alkylphenyl and alkoxyphenyl groups, R is selected from the foregoing class and lower alkoxy groups, Z is selected from the class consisting of the N= radicle and the CH= radicle, n is selected from nought and 1, m is selected from nought, l, 2 and 3, and D is a residue selected from the class consisting of five-membered and six-membered heterocyclic nitrogen nuclei.

. D may be the residue of any five-membered or sixmembered heterocyclic ring system including thiazoles, oxazoles, selenazoles and their polycyclic homologues groups are referred to groups, e. g. methoxy l COR; XI

2,865,917 Patented Dec. 23, 1958 with a compound of the formula:

(-(CH=CH),,,SR) or acetanilidovinyl grouping, R being an alkyl or aralykyl group, Xbeing an acid radicle and the other symbols having the meanings assigned. to them above.

The merocyanine dyes are valuable. optical sensitisers for silver halide photographic emulsions, and the invention emulsions (and photographic elements containing the same) which contain such dyes in sensitising amount.

The following examples will serve to illustrate the in vention. The intermediate 3-benzoyl-1-phenyl-2-thiohydantoin may be made by the method disclosed in J. Chem.

1956, page 188. The intermediate 3-benzoyl-lmethyl-2-thiohydantoin, M. Pt. 134-136 EXAMPLE 1 Z-methylbenzthiazole (1.5 gm.) and methyl p-to-Iuene I bromlde emulsion the sensitivity was extended to 6200 A" ethanol (20 ml.) and EXAMPLE 2 3-benz0yl-1-phenyl-2-th.i0-5 (3-ethy l-2 :3-dihydro 2- benzthiazolylidene) ethylidene] thiohyda-ntoin The compound was prepared as Example 1 except that 2-methyl benzthiazole ethiodide (2.0 gm.) was-used in place of Z-methyl benzthiazole metho p-toluene sulphonate.

C. was crysof ethanol mls.) and chloroform (30 ml.) and obtained as purple needles (0.8 gm.)

en incorporated in. a silver the sensitivity was extended to 6450 A. with a maximum at 6200 A, whilst in a silver chlorobromide the sensitivity extended to 6400' A. with a maximum. at 5900 A,

EXAMPLE 3 3-benzoyl-I-phenyl-2-thi0-5 (3-methyl-2 :3-dihydro-2- benzoxazolylidene) ethylidene] thiohydantoin The compound was prepared as in Example 1, but starting with Z-methylbenzoxazole metho p-toluene sulphonate (3.2 gm.). The crude dye (2.7 gm., M. Pt. 231- 232 C.) crystallised from 1200 mls. of ethanol as purple red crystals (1.3 gm.) with M. Pt. 270273 C. When incorporated in a silver iodobromide emulsion the sensitivity was extended to show a maximum at 5750 A., whilst in a silver chlorobromide the sensitivity extended to 5650 A..with a maximum at 5450 A.

EXAMPLE 4 3-benzoyl-1-phenyZ-Z-thio-S-f (3-ethyl-2 :3-dihydro-2- benzoxazolylidene ethylidenel thiohydantojn The compound was prepared as in Example 1, but starting with Z-methyl benzoxazole etho-p-toluene sulphonate The crude dye (1.9 gm.) crystallised from a mixture of ethanol (400 ml.) and chloroform (60 mls.) as purple needles (0.8 gm.) with M. Pt. 290-292 C. When incorporated in a silver iodobromide emulsion the sensitivity was extended to 6000 A. with a maximum at 5850 A., whilst in a silver chlorobrornide the sensitivity extended to 5850 A. with a maximum at 5500 A.

EXAMPLE 5 3-benz0yl-I-phenyl-2-thi0-5-[ (3-melhyl-2-thiazolidinylidene) ethylidene] thiohydantoin The compound was prepared in the same way as Example 1 except that the starting material was Z-methylthiazoline metho-p-toluene sulphonate (2.9 gm.), and the dye condensation carried out in mls. of ethanol. The crude dye (1.3 gm., M. Pt. 245249 C.) was boiled with ethanol (250 ml.) and the residue crystallised from chloroform (75 ml.) from which the product separated as a red powder (0.45 gm.) with M. Pt. 265-268 C. When incorporated in a silver chlorobromide emulsion the sensitivity was extended to 5650 A. with a maximum at 5300 A.

EXAMPLE 6 3-benz0yl-1-phenyl-2-thio-5 (3-ethyI-Z-thiazolidinylidene) ethylidene] thiohydantoin The compound was prepared in the same way as Example 1, except that the starting material was 2-methylthiazoline etho-p-toluene sulphonate and the dye condensation carried out in 10 mls. of ethanol. The crude dye (1.2 gm.) was dissolved in a mixture of ethanol (200 mls.) and chloroform (30 mls.) from which the product separated as red crystals (0.9 gm.) with M. Pt. 247249 C. When incorporated in a silver chlorobromide emulsion the sensitivity was extended to 5650 A. with a maximum at 5250 A.

EXAMPLE 7 3-benz0yl-1 -phenyl-2-thio-5 [(1 :4 :4-trimethyl-2-pyrrolidinylidene) ethylidene] zhiohydantoin 3-benzoyl-l-phenyl-2-thiohydantoin (2.0 gm.), 2(acetanilinovinyl)-4:4-dimethyl pyrroline methiodide (2.0 gm.), ethanol (10 ml.) and triethylamine (1.4 ml.) were mixed and heated under reflux for 10 minutes. The product which separated on cooling was filtered off and washed with water followed by ethanol. The crude dye (0.7 gm.) had M. Pt. 210214 C. and after two crystallisations from ethanol was obtained as orange-red crystals (0.4 gm.) with M. Pt. 237-239 C.

EXAMPLE 8 3-ben z0yl-1-phenyl-2-thio-5 (1-ethyl-4 4-dimLethyl-2- pyrrolidinylidene) ethylia ene] 1h iohydantoin The compound was prepared as in Example 7 except that 2(aeetanilinovinyl)-4:4-dim\ethyl pyrroline eithiodide (2.1 gm.) was used in place of the methiodide. The crude dye (1.0 gm.) had M. Pt. 245-248 C. and after crystallising from a mixture of ethanol ml.) and chloroform (30 ml.) was obtained as gleaming orange plates (0.65 gm.) with M. Pt. 246-248 C.

EXAMPLE 9 3 -benz0y [-1 -methyl-5 (3 -methyl-2 :3-d ihydro-Z-benzthiazolylidene -2-tlti0h3 dant01'n 3-benzoyl-l-methyl-Z-thiohydantoin (0.59 gm.), 2- methylthiobenzthiazole metho toluene p-sulphonate (0.93 gm), ethanol (5 ml.) and triethylamine (0.35 ml.) were mixed and heated under reflux for 20 minutes. After cooling, the crude dye (M. Pt. 231-233" C.) was filtered oil and twice crystallised from benzene to give orangeyellow crystals with M. Pt. 242-244 C.

When incorporated in a silver chlorobromide emulsion the sensitivity was extended to 5050 A. with a maximum at 4550 A.

EXAMPLE 10 3-benzoyl-1-methyl-5 (1-ethyl-4 :4-dimethyl-2-pyrr0lidinylidene) ethylidenel-2-thi0hydant0in S-benzoyl-1-methyl-2-thiohydantoin (0.78 g.), 2-(acetanilinovinyl)-4:4-dimethyl pyrroline ethiodide (2.0 gm.), ethanol (10 ml.) and triethylamine (0.46 ml.) were mixed and heated under reflux for 20 minutes. After cooling, the crude product (M. Pt. 180l82 C.) was filtered off and twice crystallised from ethanol to give scarlet plates with M. Pt. 194195 C.

When incorporated in a silver chlorobromide emulsion the sensitivity was extended to 5350 A. with a maximum at 5000 A.

EXAMPLE 11 3-benzoyl-1-methyl-5 (3-methyl-2 :3-dihydro-2-benzoxazolylidene) ethylidenel-2-thi0hydant0in 3-benz0yl-1-methyl-5(1-meZhyl-Z-quinolylidene) Z-thiohydantoin 2-methylthioquinoline (0.88 gm.) and methyl toluene p-sulphonate (0.95 gm.) were mixed and fused at 100 C. for 2 hours. After stirring the melt with dry ether and decanting off, 3-benzoyl-l-methyl-Z-thiohydantoin (0.78 gm), ethanol (10 ml.) and triethylamine (0.46 ml.) were added and the whole heated under reflux for 20 minutes. After cooling, the product was filtered off (M. Pt. 238- 240 C.) and crystallised from benzene (100 ml.) to give purple crystals with M. Pt. 245-247 C.

When incorporated in a silver chlorobrornide emulsion a band of sensitivity extended from 4800 A. to 5600 A.

EXAMPLE 13 3-benz0yl-1 -methyl-5(1 -methyl-1 :4-dihydroquinaz0linylidem-4)-2-thi0hydant0in 3-benzoyl-l-methyl-Z-thiohydantoin (0.78 gm), 4- methylthioquinazoline methiodide (1.6 gm.), ethanol (10 ml.) and triethylamine (0.46 ml.) were mixed and heated under reflux for 20 minutes. After cooling, the crude product (M. Pt. 124126 C.) was filtered off, washed with water and then twice crystallised from benzene to give red crystals with M. Pt. 142144 C.

EXAMPLE 14 3-benz0yl-I -methyl-5-[ I :3 :3-trz'methylindolinylidene) ethylidene] -2-i.'1i0hydant0in 3-benzoyl-l-methyl-2-thiohydantoin (0.78 gm.), 2(acetanilinovinyl) 1:3:3-trimethyl indclenium iodide (2.2 gm.), ethanol ml.) and triethylarnine (0.46 ml.) were mixed and heated under reflux for 20 minutes. After cooling the crude product (M. Pt. 112-113 C.) was filtered off and crystallised from benzene (20 ml.) to give red crystals with M. Pt. 218-220 C.

EXAMPLE 3-benz0yl-1 -methyl-5 (3-methyI-Z-Ihiazolidinylidene) ethylidene] -2-thi0hydant0in EXAMPLE l6 3-benzoyl-1-methyl-5 (3-methyl-2:3-dihydr0-2-benzthiazolylidene) butenylidene]-2-thiohydanl0in fl-Anilino-acrolein anil hydrochloride (3.0 gm.), 3- benzoyl-l-methyl-2-thiohydantoin, doubly fused sodium acetate (0.8 gm.) and acetic anhydride (5 ml.) were mixed and heated over a small flame for 3 minutes.

6 Z-methylbenzthiazole methiodide (0.15 gm.), ethanol (5 ml.) and triethylamine (0.07 gm.) and the solution heated under reflux for 20 minutes. After cooling, the product was filtered off and crystallised from ethanol (20 ml.) to give blue crystals with M. Pt. 231233 C.

What we claim is:

1. The compound 3 -benzoyl-1-phenyl-2-thio-5 [(3- ethyl-2:3-dihydro-Z-benzthiazolylidene) ethylidene] thiohydantoin.

2. The compound 3 -benzoyl-l-phenyl-Z-thio-S [(3- methyl 2:3 dihydro 2 benzoxazolylidene) ethylidene] thiohydantoin.

3. The compound 3 -benzoyl-l-phenyl-2-thio-5 [(3- ethyl-Z:3-dihydro-2-benzoxazolylidene) ethylidene] thiohydantoin.

4. The compound 3 -benzoyl 1-phenyl-2-thio-5 [(3- methyl-2-thiazolidinylidene) ethylidene] thiohyantoin.

5. The compound 3 benzoyl-l-phenyl-2-thio-5 [(3- ethyl-2-thiazolidinylidene) ethylidene] thiohydantoin.

6. A merocyanine dye of the general formula:

where R is selected from the class consisting of methyl and ethyl groups, and D is a residue selected from the class consisting of benzthiazole, benzoxazole and thiazoline nuclei.

References Cited in the file of this patent 

6. A MEROCYANINE DYE OF THE GENERAL FORMULA: 